Railway car hydraulic cushioning unit with spray type discharge ports

ABSTRACT

A railway car cushioning unit comprises a cylinder and piston and piston rod assembly reciprocally positioned therein. The cushioning unit is provided with a high pressure chamber and a draft chamber both of which are in communication with a flexible boot type reservoir. The piston rod moves through a bore provided in the cylinder head and the boot type reservoir also provides a dynamic seal for the chambers. A piston is provided with an elongated passage which communicates with the high pressure chamber through a metering orifice. Ports are provided for communicating the passageway with the flexible boot for the passage of fluid therebetween. The ports are of a configuration which provides a dispersed spray during the movement of the fluid between the passageway and chambers to the reservoir.

United States Patent [1 1 Anderson et al. I

RAILWAY CAR HYDRAULIC CUSHIONING UNIT WITH SPRAY TYPE DISCHARGE PORTS Inventors: Steven A. Anderson, Elwood, 111.;

' John H. Spence, Munster, Ind.

Assignee: Incorporated, Chicago, 111.

Filed: Feb. 17, 1971 Appl. No.: 116,186

US. Cl. ..213/43, 188/298, 188/315, 188/322, 267/64 A Int. Cl. ..B61g 9/16, B61g 11/12 Field of Search ..2l3/8.43; 267/64 R, 267/64A, 65 R; 1887269., 298, 315, 322

References Cited UNITED STATES PATENTS 9/ 1966 Peterson ..2 1 3/43 8/ 1967 Peterson.. 3/1967 Ellis, Jr.

2,222,844 11/1940 Johnson ..l88/269 Primary Examiner-Drayton E. Hoffman Attomey-Hilmond O. Vogel and Richard J. Myers ABSTRACT A railway car cushioning unit comprises a cylinder and piston and piston rod assembly reciprocally positioned therein. The cushioning unit is provided with a high pressure chamber and a draft chamber both of which are in communication with a flexible boot type reservoir. The piston rod moves through a bore provided in the cylinder head and the boot type reservoir also provides a dynamic seal for the chambers. A

piston is provided with an elongated passage which communicates with the high pressure chamber through a metering orifice. Ports are provided for communicating the passageway with the flexible boot for the passage of fluid therebetween. The ports are of a configuration which provides a dispersed spray during the movement of the fluid between the passageway and chambers to the reservoir.

4 Claims, 3 Drawing Figu' res PATENTED APR 1 01973 IN VE N TORS STEVEN A. ANDERSON JOHN H. SPENCE in 5 3 mm N mm All I RAILWAY CAR HYDRAULIC CUSHIONING UNIT WITH SPRAY TYPE DISCHARGE PORTS CROSS REFERENCES TO RELATED APPLICATIONS Willis H. Knippel U.S. Pat. No. 3,568,856, dated Mar. 9, 1971.

Knippel et al. U.S. Pat. No. 3,651,953, dated Mar. 28, 1972.

Spence et al. Ser. No. 116,049 filed Feb. 19, 1971. Shaver et al. Ser. No. 116,048 filed Feb. 17, 1971.

BACKGROUND OF THE INVENTION 1. Field of the Invention The field of invention is in the art of railway cushioning devices of a type used either with a sliding sill or in a stationary sill at opposite ends of the car. More specifically, the present invention relates to end-of-car cushioning devices which are connected to a suitable coupler and provide for energy dissipation through hydraulic means.

2. Description of the Prior Art The prior art is well disclosed in the Peterson U.S. Pat. No. 3,275,164 patented Sept. 27, 1966 and U.S. Pat. No. 3,334,757 patented Aug. 8., 1967, which relate primarily to cushioning devices wherein the reservoir or low pressure chamber comprises a flexible boot which is connected at one closed end to the piston rod and is also connected at the other open end to a cylinder head through which the piston slides. The boot also eliminates the need of a sliding seal on the cylinder head.

SUMMARY It is a primary object of the present invention to provide an improved cushioning unit including a flexible boot or dynamic seal and reservoir assembly wherein fluid is directed between high pressure and draft chambers through a passage within a piston rod. The piston rod includes an improved porting arrangement. The

piston rod is provided with a plurality of diverging bores which intersect one another within the wall of the piston rod. The porting arrangement which is provided by the intersecting bores functions to provide a metered draft control during train operation. The ports provide for a dispersed plurality of sprays of fluid into the boot thus eliminating potential damage which could occur due to the high velocity forces. Non-dispersed fluid flow could result in jet impingement against the said boot structure thereby damaging the same.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now particularly to FIG. 1, a hydraulic cushioning unit particularly well-adapted for railway cars is designated by the reference character 10, and includes a hydraulic cylinder 11 comprising an outer peripheral wall 12 and an inner peripheral wall 13. One end of the cylinder 11 is closed by a cylinder head 14 and a second cylinder head 15 is disposed within the cylinder 11 toward its other end. The second cylinder head 15 also includes a cavity or pocket 16 in which a valve retainer plate 17 is positioned. THe plate 17 includes inwardly extending projections 18 which are circumferentially spaced to provide a plurality of openings 19 communicating with opening 19. A snap ring 20 secures the retainer plate 17 in position in the cavity 16. The cylinder head 15 also comprises an axially extending bore or passage 21. A valve plate 22 is positioned within the cavity 16 and is axially movable therein.

A retainer ring 23 is supported within an annular groove 24 formed in the inner walls 13 and projects inwardly into engagement with one end of the second cylinder head 15 for retaining the same against snap ring 20.

A piston 25 includes opposite sides 26 and 27. The side 26 faces a high pressure chamber A and the side 27 faces a draft chamber B. The piston 25 is reciprocally positioned within the cylinder 11 and includes a cavity 28. A threaded end portion 29 of a piston rod 30 is rigidly secured to the piston 25 and a metering valve plate 31 is disposed in the cavity 28 and movable axially therein. The valve plate 31 includes a metering orifice 32 adapted to meter fluid to a passageway 33 provided in the piston rod 30. A fluted metering pin 31' is connected to the cylinder head 14 and projects through the metering orifice 32 to provide for the metered flow of fluid from chamber A into the passageway 33. A plurality of ports 34 are provided near the opposite end of the piston rod 30 to which is connected a base plate 35. The rear ports 34 are suitably shielded by means of a deflector 36 including openings (not shown) to deflect fluid flowing through the ports 34 into a flexible boot or reservoir 38. The deflector 36 also includes a shoulder 37 which is adapted to engage a reversely folded end portion 39 of the flexible reservoir 38 to rigidly and sealingly secure the same to the piston rod 30. The deflector 36 is more specifically described in above patent application, Ser. No. 1 16,047, filed Feb. 17, 1971. The folded end portion 39 is provided with a flange 40 which is clamped between the shoulder 37 and a collar 41 rigidly connected to the piston rod 30 and thereby securely and sealingly connects the end of the flexible boot 38 to the piston rod 30.

The other end of the flexible reservoir 38 is provided with an open end portion 43 which also includes a peripheral flange 44 which is clamped against a shoulder 45 of the second cylinder head 15. A securing ring 46 engages one side of the flange 44 and is held against a shoulder or step portion 47 of the intermediate cylinder head 15. A snap ring 48 secures the ring 46 in position.

The cylinder 11 and piston and piston rod assembly may be returned to the position shown in FIG. 1 from a former closed position by means of a coil spring 49 which is disposed about the outer wall 12 of the cylinder 11. A slide ring 50 is disposed between one end of the spring 49 and stops 51 provided on the cylinder 11. The other end of the spring 49 is retained by means of stops 52 provided on the outer wall 12 of the cylinder 1 1.

As best shown in FIGS. 2 and 3, an improved porting arrangement is shown by means of a plurality of converging bores 54 which are in communication at laterally spaced points with the passageway 33 by means of openings 55. The converging bores 54 meet or intersect within the wall of the piston rod 30 and provide a single opening 56 for each of the sets of converging bores 54 to communicate with the interior of the flexible boot 38 and draft control chamber.

THE OPERATION The hydraulic cushioning unit disclosed in FIG. 1 may be utilized as an end-of-car cushion disposed at opposite ends of a conventional center sill of a railway car. Each cushioning unit has its cylinder head 14 suitably connected to a yoke and coupler arrangement and the base plate ,35 is suitably rigidly connected against longitudinal movement within the center sill. The cylinder 11 is movable relative to the piston 25 and the sliding ring 50 may be suitably engageable with stops provided on the center sill so that during movement of the cylinder 11 the spring 49 is thereby compressed and which later again returns the cylinder 11 to its open position. Upon an impact on the cylinder the same moves to the left as shown in FIG. 1 whereupon fluid in the high pressure chamber A is metered through the metering orifice 32 into the passageway 33. Fluid flows through the ports 34 and through the deflector 36, as best described in the aforementioned related applications, Ser. Nos. 116,047 and 116,048. Fluid also flows from the passageway 33 through the converging bores 54 and outwardly through the openings 56. By virtue of the converging relation of the bores 54 a finely divided spray results as it emerges through the openings 56 into the boot 38. This eliminates jet impingement which would be effected by a single bore against the boot 38, and thus cause possible damage. By virtue of the arrangement, fine spray streams prevent damage to the boot and assures long maintenance-free life. During the impact stroke fluid flows through the bore 21 past the valve retainer plate 17 and to the draft chamber B on the side 27 of the piston 25. The operation of the valve plate 22 is not described in detail since this is clearly disclosed in the above referenced related applications. The primary function of the intersecting bores 54 and related openings or ports 55-56 is to control draft motion 'of the two-way end-of-car cushioning unit disclosed. These ports during draft provide a metered flow of fluid from the draft chamber B into chamber A through the passageway 33. The .invention resides in the intersection of the bores 54 within the wall of the piston rod to thereby decrease the velocity flow of fluid from the ports 56 during the buff forces, at which time these ports have moved into boot or reservoir and direct impingement of high velocity could be damaging to the wall of the flexible reservoir.

During train operations wherein the piston of the end-of-car cushioning units are constantly reciprocating, there is thus continued movement in buff and draft directions. The piston may be positioned in a manner wherein the ports 56 are all disposed in the 1 draft chamber B. As the piston moves back and forth there is constant metered flow through the ports 56 and upon a sudden sustained buff impact these ports 56 may be within the boot reservoir and fluid flow from the passage 33 now is outwardly of the ports 56 into the boot reservoir. It is at this time that the dispersed lower velocity flow which is provided by the invention is effective to reduce possible boot damage. The number of the ports 56 and bores 54 is determined by the draft control requirements. Thus more or less may be utilized.

Thus the primary objective of the invention has been achieved by the converging arrangement of the bores which provide for a very well dispersed spray of fluid when fluid is going from the passageway 33 to the flexible reservoir 38.

What is claimed is:

, 1. In a hydraulic cushioning device for railway cars including: I

a hydraulic cylinder including a first cylinder head adjacent one end thereof,

a second cylinder head disposed within said cylinder between an opposite open end of said cylinder and said first cylinder head,

said second cylinder head having a longitudinal opening therethrough,

a piston slidingly positioned between said cylinder heads and providing on one side of said piston a high pressure chamber,

a piston rod connected to said piston and positioned for sliding movement through said longitudinal opening,

said rod having a passageway,

metering means between said piston and said high pressure chamber providing for the metered flow of fluid from said chamber through said passageway during a buff impact,

a flexible tubular reservoir having an open end portion,

means sealingly connecting the other end of said tubular reservoir to said piston rod,

second means connecting the open end portion of said reservoir to said second cylinder head, to provide for communication between said reservoir through said longitudinal opening with a draft chamber disposed on an opposite side of said piston, the improvement comprising:

diffusing means including first and second bores intersecting within said piston rod and communicating with said passageway and said reservoir to convey fluid from said draft chamber and to disperse the same to said reservoir in a spray configuration.

2. The invention in accordance with claim 1,

said bores having openings laterally spaced at their point of communication with said passageway and at their point of communication with said reservoir providing a single opening.

3. The invention in accordance with claim 1,

with said bores at theirpoint of communication with said passageway being laterally spaced and providing a pair of openings, and

said bores converging and intersecting each other in said piston rod at a point providing a single opening communicating directly with said reservoir.

4. The invention in accordance with claim 1,

said bores being disposed in relative converging relation.

l Il 

1. In a hydraulic cushioning device for railway cars including: a hydraulic cylinder including a first cylinder head adjacent one end thereof, a second cylinder head disposed within said cylinder between an opposite open end of said cylinder and said first cylinder head, said second cylinder head having a longitudinal opening thereThrough, a piston slidingly positioned between said cylinder heads and providing on one side of said piston a high pressure chamber, a piston rod connected to said piston and positioned for sliding movement through said longitudinal opening, said rod having a passageway, metering means between said piston and said high pressure chamber providing for the metered flow of fluid from said chamber through said passageway during a buff impact, a flexible tubular reservoir having an open end portion, means sealingly connecting the other end of said tubular reservoir to said piston rod, second means connecting the open end portion of said reservoir to said second cylinder head, to provide for communication between said reservoir through said longitudinal opening with a draft chamber disposed on an opposite side of said piston, the improvement comprising: diffusing means including first and second bores intersecting within said piston rod and communicating with said passageway and said reservoir to convey fluid from said draft chamber and to disperse the same to said reservoir in a spray configuration.
 2. The invention in accordance with claim 1, said bores having openings laterally spaced at their point of communication with said passageway and at their point of communication with said reservoir providing a single opening.
 3. The invention in accordance with claim 1, with said bores at their point of communication with said passageway being laterally spaced and providing a pair of openings, and said bores converging and intersecting each other in said piston rod at a point providing a single opening communicating directly with said reservoir.
 4. The invention in accordance with claim 1, said bores being disposed in relative converging relation. 